Photoredox-Catalyzed C–H Functionalization Reactions

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 1925 - 2016

Published: Sept. 29, 2021

The fields of C–H functionalization and photoredox catalysis have garnered enormous interest utility in the past several decades. Many different scientific disciplines relied on strategies including natural product synthesis, drug discovery, radiolabeling, bioconjugation, materials, fine chemical synthesis. In this Review, we highlight use reactions. We separate review into inorganic/organometallic catalysts organic-based catalytic systems. Further subdivision by reaction class─either sp2 or sp3 functionalization─lends perspective tactical for these methods synthetic applications.

Language: Английский

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Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(8), P. 4237 - 4352

Published: Jan. 24, 2023

The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C–H functionalization approaches that make use low energy photons as a controllable source. Compared to traditional strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- chemoselectivities. Merging compelling benefits with workflow offers potentially unmatched arsenal tackle drug development campaigns beyond. This Review highlights photocatalytic strategies small-molecule drugs, agrochemicals, natural products, classified according targeted bond newly formed one. Emphasis is devoted identifying, describing, comparing main mechanistic scenarios. draws critical comparison between established ionic chemistry photocatalyzed radical-based manifolds. aims establish current state-of-the-art illustrate key unsolved challenges be addressed in future. authors aim introduce general readership functionalization, specialist practitioners evaluation methodologies, potential for improvement, future uncharted directions.

Language: Английский

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Photoinduced intermolecular hydrogen atom transfer reactions in organic synthesis

Chem Catalysis, Journal Year: 2021, Volume and Issue: 1(3), P. 523 - 598

Published: May 24, 2021

Language: Английский

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Enantioselective Radical Reactions Using Chiral Catalysts

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 5842 - 5976

Published: Jan. 24, 2022

Benefiting from the impressive increase in fundamental knowledge, last 20 years have shown a continuous burst of new ideas and consequently plethora catalytic methods for enantioselective radical reactions. This review aims to provide complete survey progress achieved over this latter period. The first part focuses on use chiral organocatalysts, these include catalysts covalently linked substrate those that interact with by weaker interactions like hydrogen bonds. second is devoted transition-metal redox catalysis which organized according increasing atomic number first-row transition metals (Ti, Cr, Fe, Mn, Co, Ni, Cu). Bioinspired manganese- iron-mediated hydroxylations oxidations are also discussed. A specific section dedicated reactivity Ru, Rh, Ir complexes as Lewis acids special focus at metal. Absorption photons result different events such energy transfer, single-electron hydrogen-atom transfer facilitating formation radicals. Organocatalysis has been successfully combined photocatalysts, opened pathways enlarging precursors available. merger photocatalysis organo- or metalla-photocatalysis brought novelty allowed discovery large original transformations. enzyme-catalyzed reactions involving intermediates largely benefit visible-light irradiation included review. provides comprehensive inventory goal detailing reaction mechanisms involved transformations any nonspecialist could find their own creativity invent yet unknown applications.

Language: Английский

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Recent advances in transition-metal-catalysed asymmetric coupling reactions with light intervention

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(22), P. 12808 - 12827

Published: Jan. 1, 2021

Transition metal-catalysed asymmetric coupling has been established as a robust tool for constructing complex organic molecules. Although this area extensively studied, the development of efficient protocols to construct stereogenic centres with excellent regio- and enantioselectivities is highly desirable remains challenging. Asymmetric transition metal catalysis light intervention provides practical alternative strategy current methods considerably expands synthetic utility result abundant feedstocks mild conditions. This tutorial review comprehensively summarizes recent advances in transition-metal-catalysed reactions intervention; particular, concise analysis substrate scope mechanistic scenarios governing stereocontrol discussed.

Language: Английский

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Using Data Science To Guide Aryl Bromide Substrate Scope Analysis in a Ni/Photoredox-Catalyzed Cross-Coupling with Acetals as Alcohol-Derived Radical Sources

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(2), P. 1045 - 1055

Published: Jan. 5, 2022

Ni/photoredox catalysis has emerged as a powerful platform for C(sp2)–C(sp3) bond formation. While many of these methods typically employ aryl bromides the C(sp2) coupling partner, variety aliphatic radical sources have been investigated. In principle, reactions enable access to same product scaffolds, but it can be hard discern which method because nonstandardized sets are used in scope evaluation. Herein, we report Ni/photoredox-catalyzed (deutero)methylation and alkylation halides where benzaldehyde di(alkyl) acetals serve alcohol-derived sources. Reaction development, mechanistic studies, late-stage derivatization biologically relevant chloride, fenofibrate, presented. Then, describe integration data science techniques, including DFT featurization, dimensionality reduction, hierarchical clustering, delineate diverse succinct collection that is representative chemical space substrate class. By superimposing examples from published on this space, identify areas sparse coverage high versus low average yields, enabling comparisons between prior art new method. Additionally, demonstrate systematically selected quantify population-wide reactivity trends reveal possible functional group incompatibility with supervised machine learning.

Language: Английский

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Modular Access to Chiral α-(Hetero)aryl Amines via Ni/Photoredox-Catalyzed Enantioselective Cross-Coupling

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(19), P. 8797 - 8806

Published: May 3, 2022

Chiral α-aryl N-heterocycles are commonly found in natural products, pharmaceutical agents, and chiral catalysts but remain challenging to access via asymmetric catalysis. Herein, we report a general modular approach for the direct enantioselective α-arylation of saturated azacycles acyclic N-alkyl benzamides nickel/photoredox dual This process exploits hydrogen atom transfer ability photoeliminated chlorine radicals convert corresponding α-amino alkyl that then coupled with ubiquitous inexpensive (hetero)aryl chlorides. These coupling reactions require no oxidants or organometallic reagents, feature feedstock starting materials, broad substrate scope, high enantioselectivities, applicable late-stage diversification medicinally relevant complex molecules. Mechanistic studies suggest nickel catalyst uncommonly plays multiple roles, accomplishing radical generation, capture, cross-coupling, induction.

Language: Английский

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Electrophotocatalytic Decoupled Radical Relay Enables Highly Efficient and Enantioselective Benzylic C–H Functionalization

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(47), P. 21674 - 21682

Published: Nov. 17, 2022

Asymmetric sp3 C–H functionalization has been demonstrated to substantially expedite target molecule synthesis, spanning from feedstocks upgradation late-stage modification of complex molecules. Herein, we report a highly efficient and sustainable method for enantioselective benzylic cyanation by merging electrophoto- copper catalysis. A novel catalytic system allows one independently regulate the hydrogen atom transfer step radical formation speciation Cu(II)/Cu(I) effectively capture transient intermediate, through tuning electronic property anthraquinone-type photocatalyst simply modulating applied current, respectively. Such decoupled relay catalysis enables unified approach diverse alkylarenes, many which are much less reactive or even unreactive using existing relying on coupled relay. Moreover, current protocol is also amenable bioactive molecules, including natural products drugs.

Language: Английский

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Nickel-Catalyzed Enantioselective Electrochemical Reductive Cross-Coupling of Aryl Aziridines with Alkenyl Bromides

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(11), P. 6270 - 6279

Published: March 7, 2023

An electrochemically driven nickel-catalyzed enantioselective reductive cross-coupling of aryl aziridines with alkenyl bromides has been developed, affording enantioenriched β-aryl homoallylic amines excellent E-selectivity. This electroreductive strategy proceeds in the absence heterogeneous metal reductants and sacrificial anodes by employing constant current electrolysis an undivided cell triethylamine as a terminal reductant. The reaction features mild conditions, remarkable stereocontrol, broad substrate scope, functional group compatibility, which was illustrated late-stage functionalization bioactive molecules. Mechanistic studies indicate that this transformation conforms stereoconvergent mechanism aziridine is activated through nucleophilic halide ring-opening process.

Language: Английский

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Photoinduced Cobalt-Catalyzed Desymmetrization of Dialdehydes to Access Axial Chirality

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(12), P. 6944 - 6952

Published: March 15, 2023

Enantioselective metallaphotoredox catalysis, which combines photoredox catalysis and asymmetric transition-metal has become an effective approach to achieve stereoconvergence under mild conditions. Although many impressive synthetic approaches have been developed access central chirality, the construction of axial chirality by still remains underexplored. Herein, we report two visible light-induced cobalt-catalyzed reductive couplings biaryl dialdehydes synthesize axially chiral aldehydes (60 examples, up 98% yield, >19:1 dr, >99% ee). This protocol shows good functional group tolerance, broad substrate scope, excellent diastereo- enantioselectivity.

Language: Английский

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